In current computer devices, a plurality of peripherals are equipped to a computer, and thus a plurality of interfaces, such as USB or 1394 interface, are needed. These interfaces are connected to the computer through signal converters for data input and output. In general these interfaces are packaged in interface boxes The specification of the interface boxes are not unified so that different interfaces are placed in different interface boxes. These interface boxes are placed on table disorderedly and thus they occupy a large space. As a result, the space cannot be used effectively and an unbeautiful outlook is presented.